During the AME-D process executed in MBfRs, gaseous substrates, CH4 and O2, are directly transferred from the membrane lumen to biofilms formed on the outer surface of the membrane, while the ammonia nitrogen substrate diffuses from the bulk liquid into the interior of the biofilm and then ammonia nitrogen is oxidized to nitrite and nitrate. Nitrite and nitrate are reduced to nitrogen by denitrificans.

I don't know if the idea is feasible.